Please bear with me as I know this is long. I've just recently purchased a 2010 ML350 4matic P2 with 69k miles. This is my 5th Mercedes and so far I really enjoy it. I had a 2008 ML a few years ago and this one is much better so far.

However, I have a couple of issues I'd like you all to help me figure out.

1) There is a pretty reproducible crunch/rubbing noise that occurs when at almost full lock when steering into a bump or raised terrain, ie. turning into my driveway that has a pretty steep incline. If I go very slow, the noise is not nearly as noticeable, if present at all. Definitely body torque or suspension related during compression or rebound. It also happens when turning into a perpendicular parking spot when I'm straightening the wheels quickly from having just turned very sharp.

2) Worrying me more than the former issue is the slight vibration I feel through the steering wheel at speed. I'm not sure if I'm just being too picky or if there's actually an issue. It doesn't occur at idle, just at highway speeds and only starts to aggravate me more, or become more apparent, after driving a while as my hands tire. Honestly, it isn't THAT bad but also, at around 30-40/45 mph, I get a wha-wha-wha that sounds like tires and I get a similar rhythmic vibration in the wheel similar to the "highway" vibration. Same issue? Does the wha-wha-wha morph into a nearly constant hum, thus vibration, that is masked by wind or road noise? I don't know. Could it simply be the tires seeing as how they'll need replacing before too long anyway?

I don't know where to start. I've read about wheel bearings and differentials going bad and I don't have a clue where to begin.

What are the symptoms of either a bad wheel bearing or bad front differential so that I might can tell the difference?

I have a bumper to bumper Premier GWC warranty that covers everything the original warranty covered save a few select items that I'm aware of.

Thanks so much in advance!

 

The "beating" noise you describe is consistent with tyres. So is the vibration. Check the tyres carefully for damage or say a nail, then get them rebalanced checking for roundness at the same time.

Faulty bearings tend to give a consistent groan that varies in pitch directly with speed. This is not what you are describing. This applies to both wheel bearings and diff bearings.

The other noise has me puzzled. One thought is damage to a CV joint, but that is usually a "clicking" at extreme angles.

The other thought is that the steering angle limiter is rubbing against its stop. This was a noticeable problem on the Mitsubishi 4x4 range, but I never heard it once on the ML350CDI in 67,000 km.

Perhaps it is a suspension bush worn allowing excess movement.

 

Wow, thanks so much for the quick and detailed reply!

I'm glad to know that it's probably the tires causing my highway noise. I can handle replacing the tires but it'd be hard to stomach replacing a differential on a 2010 ML. I just haven't heard of many differential issues with the newer w164's so hopefully that's not my problem.

I guess I might have to get the "crunch" looked at. At least it's not constant and only happens during tight turns at slow parking lot speeds. It is easily reproduced so hopefully my dealer can pinpoint it fairly quickly. It might just be something that needs servicing or lubricating.

Thanks again for the reply! Let me know if you think of anything else.

 

Regarding the crunch/creaking sound, what do you guys think about the "headlight washer nozzle" theory that I've read about in previous posts regarding a return-from-full-lock steering noise?

How accessible is the headlight washer assembly to be able to even find the nozzle bracket that has been found to be the culprit in similar situations?

Just a thought.

 

Just joined and ran into your original post. I was chasing the same two problems you described for months with NTB/Merchants Tire until yesterday. Had the same crunching/rubbing noise at full lock, and vibration through the steering wheel (between 20 mph and 80mph). MB dealer found tires were balanced improperly by Merchants, found worn front control arm bushings (replaced both front control arm bushings under warranty), and performed another alignment.

Car seems much better now. Feels more solid, tracking is true, and steering wheel vibration is gone. I've only been up to 50 mph so far, but seems ok. Will test at 70-80mph this afternoon.

 

Oddly enough, I am currently in the process of getting my control arms/bushings replaced by my MB dealer in Tallahassee. They replaced the right upper control arm/bushings (I think it was upper) and I am going to have them do the left side as well. The noise is nearly 100% gone except for the fact that I hear it faintly when turning sharply to the right. The awful crunch when turning left is completely gone.

ALso, I'm going to replace my tires very soon as they're roaring and it needs an alignment since getting the work done on the front end. I figured I'd get tires/alignment/other control arm and bushings done at the same time and hopefully it'll feel like a new vehicle. Hopefully!

Thanks for your reply and I'm thankful that I wasn't the only person experiencing this issue. Maybe we found the culprit!

 

Hi guys.. I just joined the forum for the same reason as I have the same problem

It started about 2 weeks ago and I usually get the knocking / thumping sound when driving at low speeds or when I park the car

Highway driving is as smooth as silk

I went to the dealership who asked to keep the car for testing for 3 days

Unfortunately I didn't have another vehicle so I scheduled it for next week

Keep me updated please


Thanks

 

And FINALLY...

The Dealership replied with the solution

They said that the bearing and the control arms (both upper and lower) have to be changed and after that they will see if the problem is solved..

In other words they slammed a 5000$ bill in my face and said that they will keep slamming me with more

My car is a 2010 model,, purchased in April 2011

It has 34000 km ONLY

no off roading and strictly no nuisance while driving

Warranty expired about 2 months ago

The service agent said that he will try get in touch with the manufacturer regarding a "good will"!!! Which I do not know what he means


Anyhow I took the car to another workshop "certified Merc mechanic" for a second opinion


Any feedback guys!!!

 

Good job. Don't just take the dealers word for it.
How's the condition of the tires look like? Can you post any pictures of them?

 

Dear ALL

FINALLY.. Thanks God I got my car back

Thanks for you guys for the input and a special thanks to CHIKOO
For advising me to take it to another garage

The problem was diagnosed in 2 days
It was the LINK STABILIZERS

I had them changed .. I also had the brake pads changed and the car polished
thanks to the great guys at SCHNELL AUTO SERVICES

Total cost was 950$$ including parts and labor

Compared to the 5000$$ the dealer asked.. I am blessed

My question is .. Why do MB DEALERS tend to rip customers off their hard earned money
For lousy treatment and over rated services

 

That's awesome! Where exactly is the link stabilizer? Is that part of the sway bar in the rear?